A large number of rail tracks such as roller coaster tracks, bobsled tracks, wildwater tracks and so on can be found in amusement parks and fair grounds. A common feature of all these tracks is that rail vehicles are not propelled by their own drive system and that they run in a closed course. At the beginning of the closed course, the rail vehicles are pulled up an incline to a certain height. From this height they move without their own drive system, i.e., by gravity, to the end of the course. They are pulled up the incline with a traction chain, for example. Since the incline is usually very steep, the rail vehicle must be immediately prevented from rolling backward in the event of failure of the pulling mechanism. A detent pawl attached to the vehicle and pulled over a toothed rack attached to the bottom of the incline is usually used for this purpose. The detent pawl is raised by one flank of the toothed structure, and after passing the descending flank, drops under gravity into the gaps between the teeth. Loud clattering that can be heard far away is associated with this dropping-back action.
Since show businesses of this type, particularly fair grounds, are erected in the vicinity of residential districts, this noise production is extremely annoying. It is during the night time sleeping periods in particular that residents are subjected to such additional noise production.
This clattering noise is extremely annoying even for the passengers of the rail vehicles.